Nanoparticles of a different source induce different patterns of activation in key biochemical and cellular components of the host response

Nanoparticulate materials are produced by industrial processing or engineered for specific biomedical applications. In both cases, their contact with the human body may lead to adverse reactions. Most of the published papers so far have focused on the cytotoxic effects of nanoparticles (NPs). Instead, the present in vitro study investigates the effect of different types of NP on key components of the host response such as clot formation and the inflammatory cells. The different NPs were pre-conditioned with platelet-rich human plasma for 30 min and then incubated with the blood mononuclear cells for 20 hours. The potential of the different NPs to induce clot formation, platelet activation and monocyte/macrophage differentiation was assessed by morphological analysis, immunocytochemistry and biochemical assays. The data showed that nanoparticulate materials based on antimony, silver and nickel were capable of promoting the polymerization of fibrin and the aggregation and fragmentation of platelets, leading to a moderately activated monocyte phenotype. This process was more pronounced in the case of antimony- and silver-based NPs that share a similar size and round-shaped morphology. Conversely, NPs of cobalt, titanium and iron appeared to stimulate cells to acquire a macrophage phenotype able to secrete higher levels of tumour necrosis factor α, a pro-inflammatory cytokine. Therefore, the present study provides clear indications about the subtle and adverse effects that the invasion of these materials may produce in the cardiovascular system and in vital organs.     

Physicochemical characterization of solid dispersions of indomethacin with PEG 6000, Myrj 52, lactose, sorbitol, dextrin, and Eudragit E100

The purpose of this study was to prepare and characterize solid dispersions of indomethacin with polyethylene glycol (PEG) 6000, Myrj 52, Eudragit® E100, and different carbohydrates such as lactose, mannitol, sorbitol, and dextrin. Indomethacin is a class II substance according to the Biopharmaceutics Classification System. It is a poorly water soluble antirheumatic agent. The goal was to investigate whether the solid dispersion can improve the dissolution properties of indomethacin. The solid dispersions were prepared by three different methods depending on the type of carrier. The evaluation of the properties of the dispersions was performed using solubility measurements, dissolution studies, Fourier-transform infrared spectroscopy, and x-ray powder diffractometery. The results indicate that lactose, mannitol, sorbitol, and especially Myrj 52 are suitable carriers to enhance the in vitro dissolution rate of indomethacin at pH 7.2. Eudragit E100, Myrj 52, and mannitol increase the dissolution properties at pH 1.2. The data from the x-ray diffraction showed that the drug was still detectable in its solid state in all solid dispersions except solid dispersions with dextrin and high amounts of mannitol. However, the results from infrared spectroscopy together with those from x-ray diffraction showed well-defined drug-carrier interactions for dextrin coevaporates.     

Fabrication,characterization and in vitro drug release behavior of electrospun PLGA/chitosan nanofibrous scaffold

In this study both aligned and randomly oriented poly(d,l-lactide-co-glycolide) (PLGA)/chitosan nanofibrous scaffold have been prepared by electrospinning. The ratio of PLGA to chitosan was adjusted to get smooth nanofiber surface. Morphological characterization using scanning electron microscopy showed that the aligned nanofiber diameter distribution obtained by electrospinning of polymer blend increased with the increase of chitosan content which was similar to that of randomly oriented nanofibers. The release characteristic of model drug fenbufen (FBF) from the FBF-loaded aligned and randomly oriented PLGA and PLGA/chitosan nanofibrous scaffolds was investigated. The drug release rate increased with the increase of chitosan content because the addition of chitosan enhanced the hydrophilicity of the PLGA/chitosan composite scaffold. Moreover, for the aligned PLGA/chitosan nanofibrous scaffold the release rate was lower than that of randomly oriented PLGA/chitosan nanofibrous scaffold, which indicated that the nanofiber arrangement would influence the release behavior. In addition, crosslinking in glutaraldehyde vapor would decrease the burst release of FBF from FBF-loaded PLGA/chitosan nanofibrous scaffold with a PLGA/chitosan ratio less than 9/1, which would be beneficial for drug release.     

Well-designed WO3/Activated carbon composite for Rhodamine B Removal: Synthesis,characterization, and modeling using response surface methodology

This study focuses on the preparation of WO₃ oxide nanoparticle/Activated carbon composite (WO₃/AC) for Rhodamine B (RhB) adsorption. The prepared samples were characterized using X-Ray Energy Dispersive Spectroscopy (EDS) and Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller surface area (BET), Raman Spectroscopy and Thermogravimetric analyses (ATG-ATD). Adsorption experiments of RhB onto WO₃/AC were carried out in a batch reactor and different operational parameters were investigated. The RhB adsorption process was well fitted by pseudo-second-order kinetic and Langmuir isotherm models (1666.67mg.g^?1). Moreover, the values of thermodynamic parameters indicate the spontaneous, endothermic and physisorption adsorption nature. Finally, adsorption mechanism was proposed on the basis Raman analyses before and after adsorption.     

Synthesis,characterization r）oly [LA-co-（GIc-alt-Lys）] for and biological evaluation of nerve regeneration scaffold

A novel nerve repairing material poly [LA-co.（GIc-alt-Lys）] （PLGL） was synthesized. The viability and growth of Schwann cells （SCs） co-cultured With poly （D, L- lactic acid） （PDLLA） films （control group） and PLGL films were evaluated by MTT assay and SEM observation. Then, contact angle measurement, histological assessment and enzyme-linked immunosorbent assay （ELISA） testing on inflammatory-related cyto- kines such as IL-10 and TGF-β1 were performed. The results showed that, compared with PDLLA, PLGL films possesses better hydrophilicity, biocompatibility, degradation property and less inflammatory reaction. The present study indicated that PLGL scaffolds would meet the requirements of artificial nerve scaffold and have a potential application in the fields of nerve regeneration.     

Preparation,characterization, in vitro bioactivity and protein loading/release property of mesoporous bioactive glass microspheres with different compositions

Mesoporous bioactive glass microspheres (MBGMs) with large mesopores have attracted considerable attention in the field of bone tissue regeneration and drug delivery systems due to their excellent bioactivity, biocompatibility and high specific area. In this study, a loose structure of MBGMs with adjustable chemical compositions was synthesized by the combination of sol-gel and water-in-oil (W/O) microemulsion. All the prepared MBGMs possessed a large mesopore diameter that increased with CaO content, a high surface area and good apatite-inducing formation ability. In vitro protein absorption and release assays demonstrated that the MBGMs exhibited decreased loading efficiency and burst release behavior as the CaO content increased. Additionally, an enhanced BSA-loading amount and prolonged release curve were obtained after the surfaces of MBGMs were modified by amine groups. Furthermore, the preliminary in vitro cell experiments showed that MBGMs exhibited good biocompatibility. The results indicated that MBGMs could be a promising candidate as a drug/protein carrier for bone tissue regeneration.     

Physico/chemical characterization and preliminary human histology assessment of a β-TCP particulate material for bone augmentation

This study aimed to physico/chemically characterize and evaluate the in vivo performance of a β-TCP particulate grafting material. SEM/TEM, and EDS and XPS were used for morphology and chemistry assessment, respectively. FTIR was used to determine Ca–P phases characteristic bands. Rietveld refinement/XRD spectra was performed for secondary phase detection. Particle size distribution and specific surface were assessed by a scattering-laser based technique and BET, respectively. Mercury porosimetry was employed to determine pore-size distribution. For in vivo evaluation, the grafting material was used in 12 patients' sinus lifts, and biopsies were obtained at post-operative times of 3, 6, and 9 months. SEM/TEM revealed multigrained particles with interconnected pores. EDS showed Ca, P, and O, with stoichiometry close to theoretical values. XRD/Rietveld showed that the material presented crystalline β-TCP with ~ 9% β-Ca₂P₂O₇ secondary phase. FTIR did not detect the presence of bands related to α-TCP. Human histologic assessment showed that newly formed bone was present at 3 months, and degrees of bone organization increased as time elapsed in vivo. Human histology showed that the material is suitable for bone regeneration in a maxillofacial complex region.     

Deposition, characterization and biological application of epitaxial Li:ZnO/Al:ZnO double-layers

Double-layers of lithium doped ZnO (LZO) and aluminum doped ZnO (AZO) are grown on r-cut sapphire (r-Al₂O₃) crystal substrates by pulsed-laser deposition. The epitaxial double-layers are a-axis lattice oriented to the substrate. The LZO/AZO/r-Al₂O₃ samples have high optical transmission in the visible range and a bandgap energy of E_g = 3.28 eV according to the absorption edge of ZnO. The AZO bottom layers are electrically conductive (resistivity at room temperature ρ ~ 10^− 3 Ω cm) and LZO top layers are highly resistive (ρ ≥ 10⁵ Ω cm). Acoustic shear mode resonances in r-Al₂O₃ are excited by employing electric fields to the piezoelectric LZO layer (frequency interval 1.5-3 GHz). For biological applications, Madin-Darby canine kidney cells are cultivated on Platinum coated LZO/AZO/r-Al₂O₃ samples. Osmotic pressure applied to the cells increases or reduces the cell volume depending on the osmolarity of the medium.     

Nanostructured lipid carriers loaded with simvastatin: effect of PEG/glycerides on characterization,stability, cellular uptake efficiency and in vitro cytotoxicity

Objective: The aim of this study is to evaluate the use of PEG/glycerides of different HLB; oleoyl macrogol-6-glycerides (Labrafil^® M 1944 CS) and caprylocaproylmacrogol-8-glycerides (Labrasol^®), compared to Labrafac lipophile^® as PEG-free glyceride in the preparation of nanostructured lipid carriers (NLCs). PEG/glycerides are suggested to perform a dual function; as the oily component, and as the PEG-containing substrate required for producing the PEGylated carriers without physical or chemical synthesis.

Methods: Lipid nanocarriers were loaded with simvastatin (SV) as a promising anticancer drug. An optimization study of NLC fabrication variables was first conducted. The effect of lyophilization was investigated using cryoprotectants of various types and concentrations. The prepared NLCs were characterized in terms of particle size (PS), size distribution (PDI), zeta potential (ZP), drug entrapment, in vitro drug release, morphology and drug–excipient interactions. The influence of glycerides?±?PEG on the cytotoxicity of SV was evaluated on MCF-7 breast cancer cells, in addition to the cellular uptake of fluorescent blank NLCs.

Results: The alteration between different oil types had a significant impact on PS, ZP and drug release. Both sucrose and trehalose showed the lowest increase in PS and PDI of the reconstituted lyophilized NLCs. The in vitro cytotoxicity and cellular uptake studies indicated that SV showed the highest antitumor effect on MCF-7 cancer cells when loaded into Labrasol^® NLCs demonstrating a high cellular uptake as well.

Conclusion: The study confirms the applicability of PEG/glycerides in the development of NLCs. Encapsulating SV in Labrasol^®-containing NLC could enhance the antitumor effect of the drug.     

Characteristics and in vitro biological assessment of (Ti, O, N)/Ti composite coating formed on NiTi shape memory alloy

In this investigation, plasma immersion ion implantation and deposition (PIIID) was used to fabricate a (Ti, O, N)/Ti coating on NiTi shape memory alloy (SMA) to improve its long-term biocompatibility and wear resistance. The surface morphology, composition and roughness of uncoated and coated NiTi SMA samples were examined. Energy dispersive X-ray elemental mapping of cross-sections of (Ti, O, N)/Ti coated NiTi SMA revealed that Ni was depleted from the surface of coated samples. No Ni was detected by X-ray photoelectron spectroscopy on the surface of coated samples. Furthermore, three-point bending tests showed that the composite coating could undergo large deformation without cracking or delamination. After 1 day cell culture, SaOS-2 cells on coated samples spread better than those on uncoated NiTi SMA samples. The proliferation of SaOS-2 cells on coated samples was significantly higher at day 3 and day 7 of cell culture.     

Substitution of Cu by Fe in the superconducting ceramic oxide EuBa2Cu3Oy: Structure, electrical conductivity, and microwave response

A series of EuBa₂(Cu_1–x Fe _x )₃O_y (0.0x0.15) ceramics were prepared and examined by thermogravimetric analysis, X-ray powder diffraction, electrical resistance measurements, and a magnetically modulated microwave absorption technique. The oxygen content (y=6.98±0.03), determined by thermogravimetric analysis in a reducing atmosphere, was independent of the iron concentration forx0.12. The introduction of iron into the EuBa₂Cu₃O _y lattice, via substitution into copper sites, effects a progressive decrease in the superconducting transition temperature with increasing iron concentration. Normal-state conductivity similarly progresses from a low resistivity and negative temperature coefficient behavior, to a semiconducting-like response at the high iron concentrations. X-ray powder diffraction measurements indicate that material containing 6% iron and above is tetragonal, yet it remains superconducting with up to at least 12% iron.